O-Linked N-acetyl glucosamine (O-GlcNAc) is a sugar that is attached to a large number of different proteins that cells use to signal genes to turn on or off in response to nutrients and stress. Eliminating O-GlcNAc is lethal to mammals. Furthermore, incorrect cellular signaling resulting from faulty attachment of O-GlcNAc is linked to numerous human diseases, including neurodegeneration, diabetes, and cancer. With this award, the Chemistry of Life Processes Program in the Chemistry Division is funding Dr. Christina Woo from Harvard University to study and interpret an “O-GlcNAc codeâ€, the biochemical rules by which the addition or removal of O-GlcNAc affects signaling in living cells. Dr. Woo attaches small antibodies (called nanobodies) to enzymes that attach or remove O-GlcNAc from other proteins. These nanobodies are designed to bring these modifying enzymes to specific target proteins and, in this way, systematically determine how introducing or eliminating O-GlcNAc affects the biochemical mechanisms of cell signaling. The new mechanistic understandings from this research project will impact the interpretation of the O-GlcNAc code, and its potential use as biomarkers and in the design of new therapies against human diseases. This research will provide graduate students with specialized training in the chemistry of sugars in biology (glycoscience). In addition, the outreach program of the project introduces elementary and middle school students, along with primary school teachers to the science of sugars (glycosciences) and the influence of sugars in life processes, using a hands-on “Is it sugar?†laboratory experience.
This research project aims to decode cellular signaling through O-linked N-acetyl glucosamine (O-GlcNAc) using nanobodies as a mechanism to systematically alter the O-GlcNAc code in living cells. O-GlcNAc is an essential post-translational modification, yet the regulation of all O-GlcNAc proteins by only two enzymes, O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), has limited the study of O-GlcNAc signaling and dynamics in cells. The primary hypothesis is that nanobody fusions to OGT or OGA could serve as an orthogonal mechanism to tune O-GlcNAc levels and protein selection in live cells, and thus transform the elucidation of O-GlcNAc signaling. The research project implements chemical glycoproteomics and nanobody technology as tools to probe O-GlcNAc levels on proteins, with the goal to systematically evaluate hypotheses in how OGT introduces O-GlcNAc and how OGA dynamically removes O-GlcNAc to target proteins in live cells. The overall outreach and education objectives are to strengthen diversity and improve glycoscience education in the Massachusetts STEM pipeline via the development of research and educational activities aimed at students in elementary school through undergraduate levels, as well as the education of local public school teachers.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
